As to pneumatic tires, there have been known those having a structure in which a band layer is disposed outside a belt layer. For example, as shown in FIG. 8 (A), a band layer is formed by winding a narrow strip ply 4 spirally in the tire circumferential direction. The narrow strip ply 4 comprises a plurality of cords 3 embedded in rubber (g) at intervals.
On the other hand, as shown in FIG. 8 (B), the narrow strip ply 4 is formed by dividing a wide ply material (a) with a plurality of cutters (b). Typically, a primary ply material a1 which is a top fabric of about 1450 mm width is once cut and divided into secondary ply materials a2 of about 100 mm width. Thereafter, the secondary ply material a2 is further cut and divided into narrow strip plies 4 of about 10 mm width.
At this time, each narrow strip ply 4 is required to have a specified number of cords 3. Therefore, conventionally, the cords embedded in the primary and secondary ply materials a1, a2 are counted by visual observation. And, marking is made at each of positions corresponding to every specified cord number, and then, cutters (b) for dividing are set at the respective positions of the markings (for example, see Patent Document 1).
However, the counting of the cords by visual observation is poor in the working efficiency. Further, the incidence of erroneous counting becomes higher, and the accuracy and reliability are deteriorated.